ACQUISITIONS ACQUISITIONS (Details 6) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Oct. 31, 2017	Oct. 31, 2015
FY 2015 Acquisition [Member]
Business Acquisition [Line Items]
Pro Forma Revenue	$ 1,244,911
Pro Forma Net Income (Loss) Attributable to HEICO	$ 163,012
Pro Forma Net Income (Loss) Per Share Attributable To Common Shareholders [Abstract]
Pro Forma Earnings Per Share, Basic	$ 1.69
Pro Forma Earnings Per Share, Diluted	$ 1.66
Pro Forma Net Income Attributable to Parent	$ 140,771
Electronic Technologies Group [Member] \| Robertson [Member]
Business Acquisition [Line Items]
Pro Forma Revenue		$ 1,275,926
Pro Forma Net Income (Loss) Attributable to HEICO		$ 162,645
Pro Forma Net Income (Loss) Per Share Attributable To Common Shareholders [Abstract]
Pro Forma Earnings Per Share, Basic		$ 1.71
Pro Forma Earnings Per Share, Diluted		$ 1.68
Pro Forma Net Income Attributable to Parent		$ 142,445

Business Acquisition Pro Forma Net Income (Loss) Per Share Attributable To Common Shareholders

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Pro Forma Net Income Attributable to Parent

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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